A man threatened to '"drive his car into Downing Street" after a government pledge of £16 billion for the military sent him into a fury, a court heard.
During the incident on November 20 last year Gerald Dennis, 44, told one frightened bystander at a petrol station not to "hate me when you see me on TV tomorrow."
He was heard to say: "I hate Boris, I'm gonna drive my car into 10 Downing Street. Don't hate me."
Northamptonshire Police officers caught up with Dennis a short while later, when he played off his comments at an Asda petrol station as a "joke" Northants Live reports.
The case was heard in his absence at Northampton Magistrates Court on Monday where details of the chilling effect his behaviour had on a psychiatric nurse who overheard him that night were revealed.
Kirsty Gordon-Cleaver, prosecuting, said: "At 7.15pm, police were deployed to reports of a male, who told a member of public that he had intended to drive his car into Number 10 Downing Street.
"The suspect vehicle was a Red Seat Ibiza. At around 8.40pm, it was sighted on the A45 for Raunds towards Rushden.
"They stopped the vehicle and the officer immediately exited the vehicle and took control of the driver, who identified himself as Erwin Dennis."
Ten minutes later, Dennis, of Rushden, was arrested on suspicion of terrorist offences after they told him of the allegation.
He replied: "That was a joke. I'm not ready to kill Boris, of course I'm not. I'm not happy with him, like many other people", the court heard.
Mrs Gordon-Cleaver said: "He said 'look how far I am from Number 10 - you really think I could do that? It is ridiculous.'"
The initial comments had been heard by a psychiatric nurse at the Asda petrol station in Rushden.
In a statement, the bystander at Asda petrol station said: "He was carrying his car keys. I've never seen this male before but I would recognise him if I saw him again.
"I was filling up my car with petrol. His car was parked at the fuel pump in front of me - a red Seat Leon.
"I saw the man coming out to the shop on the forecourt and he starts walking towards me. I could hear him laughing to himself."
The man thought Dennis "might be on the phone" at first before he looked at the witness "dead in the eye"
They added: "I was confused. He said 'don't hate me when you see me on TV tomorrow. I hate Boris, I'm gonna drive my car into 10 Downing Street. Don't hate me.'
"He spoke with a British accent. His tone was calm and he spoke in a regular way. He was not manic at all.
"I felt terrified and scared because of the context of what he said - like he was going to carry it out.
"I work as a mental health nurse and I've seen patients carry out horrible things that they say they're going to do.
"The man seemed pretty intent and confident that he was going to do it. He was convincing.
"I heard him say 'I'm doing us all a favour.' I saw man for around 30 seconds in total. I got my phone, called 999 and told the police what just happened."
When interviewed by officers, Dennis said he had been talking about the state of the country with a friend.
The court was told the government had announced they would be spending £16 billion on the military, which annoyed him as he had not been working.
Mrs Gordon-Cleaver: "His upcoming job had been delayed due to Covid and he was frustrated. He cares for his mother.
"His partner previously committed suicide in the past. It just came out and he was particularly frustrated.
"He said he didn't mean to cause alarm or distress but understands it did. He had no intention of going to 10 Downing Street.
"He knew he would be shot before he even got close to the premises. He was just frustrated and apologetic."
At interview, Dennis said he "doesn't like Boris" but is "not a violent person" and was just "voicing his frustration".
He was convicted of using threatening/abusive words/behaviour likely to cause harassment, alarm or distress.
Sentencing, magistrates issued a 12-month conditional discharge, along with £85 court costs and a £22 victim surcharge.
